Materials and methods for mitigating the harmful effects of blue light

ABSTRACT

Provided herein are optically transparent materials configured to block an appropriate amount of incident blue light such that when the materials are positioned in the optical path between environmental light and the retina of a user, the optically transparent materials reduce the amount of blue light from the environmental light that reaches the retina of a user. The materials can block an effective amount of blue light to minimize damage to retinal tissue while permitting transmission of an effective amount of maintain acceptable photopic vision, scotopic vision, color vision, and circadian rhythms.

BACKGROUND

The electromagnetic spectrum is the range of all possible frequencies ofelectromagnetic radiation, including radio waves, millimeter waves,microwaves, infrared, visible light, ultra-violet (UVA and UVB), x-rays,and gamma rays. The Earth's ozone layer absorbs wavelengths up toapproximately 286 nm, shielding human beings from exposure toelectromagnetic radiation with the highest energy. However, humans areexposed to electromagnetic radiation having wavelengths above 286 nm.Most of this radiation falls within the human visual spectrum, whichincludes light having a wavelength ranging from approximately 400nanometers (nm) to approximately 700 nm.

The human retina responds to visible light (400-700 nm). The shorterwavelengths of visible light pose the greatest hazard to human healthbecause they inversely contain greater energy. In particular, bluelight, ranging in wavelength from approximately 400 nm to approximately500 nm, has been shown to be the portion of the visible spectrum thatproduces the most photochemical damage to animal retinal pigmentepithelium (RPE) cells.

Cataracts and macular degeneration have been associated withphotochemical damage to the intraocular lens and retina, respectively,resulting from blue light exposure. Blue light exposure has also beenshown to accelerate proliferation of uveal melanoma cells. Recentresearch also supports the premise that short wavelength visible light(blue light) may contribute to age related macular degeneration (AMD).

The human retina includes multiple layers. These layers, listed in orderfrom the first exposed to any light entering the eye to the deepest,include:

1) Nerve Fiber Layer

2) Ganglion Cells

3) Inner Plexiform Layer

4) Bipolar and Horizontal Cells

5) Outer Plexiform Layer

6) Photoreceptors (Rods and Cones)

7) Retinal Pigment Epithelium (RPE)

8) Bruch's Membrane

9) Choroid

When light is absorbed by the human eye's photoreceptor cells, (rods andcones) the cells bleach and become unreceptive until they recover. Thisrecovery process is a metabolic process referred to as the “visualcycle.” Absorption of blue light reverses this process prematurely,increasing the risk of oxidative damage. This reversal leads to thebuildup of lipofuscin in the RPE layer of the eye. Excessive amounts oflipofuscin lead to the formation of extracellular aggregates termed“drusen” between Bruch's membrane and the RPE of the eye.

Over the course of a person's life, metabolic waste byproductsaccumulate within the RPE layer of the eye due to the interaction oflight with the retina. Metabolic waste byproducts include certainfluorophores, such as lipofuscin constituent A2E. As this metabolicwaste accumulates in the RPE layer of the eye, the body's physiologicalability to metabolize waste diminishes, and blue light stimulus causesdrusen to be formed in the RPE layer. It is believed that the drusenfurther interfere with the normal physiology/metabolic activity,contributing to AMD. AMD is the leading cause of irreversible severevisual acuity loss in the United States and Western World. The burden ofAMD is expected to increase dramatically in the next 20 years because ofthe projected shift in population and the overall increase in the numberof ageing individuals.

Drusen hinder or block the RPE layer from providing the proper nutrientsto the photoreceptors, which leads to damage or even death of thesecells. To further complicate this process, it appears that whenlipofuscin absorbs blue light in high quantities it becomes toxic,causing further damage and/or death of the RPE cells. It is believedthat the lipofuscin constituent A2E is at least partly responsible forthe short-wavelength sensitivity of RPE cells. Lipofuscin chromophoreA2E exhibits a maximum absorption of approximately 430 nm. Thephotochemical events resulting from the excitation of A2E can lead tocell death.

From a theoretical perspective, the following events appear to takeplace in the eye: (1) starting from infancy and throughout life, wastebuildup, including buildup of lipofuscin, occurs within the RPE; (2)retinal metabolic activity and the eye's ability to deal with this wastetypically diminishes with age; (3) macular pigment typically decreaseswith age, thus filtering out less blue light; (4) blue light causes theaccumulating lipofuscin to become toxic, damaging pigment epithelialcells.

The lighting and vision care industries have standards as to humanvision exposure to UVA and UVB radiation. Surprisingly, no such standardis in place with regard to blue light. For example, in the commonfluorescent tubes available today, the glass envelope mostly blocksultra-violet light but blue light is transmitted with littleattenuation. In some cases, the envelope is designed to have enhancedtransmission in the blue region of the spectrum. Such artificial sourcesof light hazard may also cause eye damage.

With a goal of protecting eyes from the potentially harmful effects ofblue light, eyewear (e.g., sunglasses, spectacles, goggles, and contactlenses) configured to block blue light has been evaluated. Such eyeweartypically employs a yellow dye or pigment (e.g., BPI Filter Vision 450or BPI Diamond Dye 500) that absorbs incident blue light. As a result,such eyewear typically includes yellow tinted lenses that completely (ornearly completely) block light below a threshold wavelength (e.g., below500 nm), while also reducing light exposure at longer wavelengths.

However, such eyewear has significant drawbacks for the user. Inparticular, blue blocking ophthalmic systems may be cosmeticallyunappealing because of a yellow or amber tint that is produced in lensesby blue blocking. To many people, the appearance of this yellow or ambertint may be undesirable cosmetically. Moreover, the tint may interferewith the normal color perception of a lens user, making it difficult,for example, to correctly perceive the color of a traffic light or sign.

Efforts have been made to compensate for the yellowing effect ofconventional blue blocking filters. For example, blue blocking lenseshave been treated with additional dyes, such as blue, red or green dyes,to offset the yellowing effect. The treatment causes the additional dyesto become intermixed with the original blue blocking dyes. However,while this technique may reduce yellow in a blue blocked lens,intermixing of the dyes may reduce the effectiveness of the blueblocking by allowing more of the blue light spectrum through. Moreover,these conventional techniques undesirably reduce the overalltransmission of light wavelengths other than blue light wavelengths.This unwanted reduction may in turn result in reduced visual acuity fora lens user.

Conventional blue-blocking also reduces visible transmission, which inturn stimulates dilation of the pupil. Dilation of the pupil increasesthe flux of light to the internal eye structures including theintraocular lens and retina. Since the radiant flux to these structuresincreases as the square of the pupil diameter, a lens that blocks halfof the blue light but, with reduced visible transmission, relaxes thepupil from 2 mm to 3 mm diameter, will actually increase the dose ofblue photons to the retina by 12.5%. Protection of the retina fromphototoxic light depends on the amount of this light that impinges onthe retina, which depends on the transmission properties of the ocularmedia and also on the dynamic aperture of the pupil.

Another problem with conventional blue-blocking is that it can degradenight vision. Blue light is more important for low-light level orscotopic vision than for bright light or photopic vision, a result whichis expressed quantitatively in the luminous sensitivity spectra forscotopic and photopic vision. Accordingly, blue-blocking eyewear thatcompletely (or nearly completely) blocks incident light below athreshold wavelength (e.g., below 500 nm) can significantly impair nightvision.

In addition, blue light is known to impact circadian rhythms. Melatonin(N-acetyl-5-methoxytryptamine) is a hormone secreted by the pinealgland. Melatonin, in part, regulates the sleep-wake cycle by chemicallycausing drowsiness and lowering the body temperature. Blue light havinga wavelength of 460 to 480 nm suppresses melatonin production.Accordingly, ensuring proper levels of blue light throughout the day canbe important for maintaining acceptable circadian rhythms.

Accordingly, there is a need for materials that can mitigate the harmfuleffects of blue light while maintaining acceptable photopic vision,scotopic vision, color vision, and circadian rhythms.

SUMMARY

Provided herein are optically transparent materials configured to blockan appropriate amount of incident blue light, such that when thematerials are positioned in the optical path between environmental lightand the retina of a user, the optically transparent materials reduce theamount of blue light from the environmental light that reaches theretina of a user.

The materials can block an effective amount of blue light to minimizedamage to retinal tissue while permitting transmission of an effectiveamount of maintain acceptable photopic vision, scotopic vision, colorvision, and circadian rhythms. The materials can also reflect at leastsome incident light across a range of wavelengths centered in the blueregion of the electromagnetic spectrum. This can improve the contrastand clarity of images viewed through the materials, reducing eyefatigue. In addition, the materials can be substantially neutral incolor (e.g., non-yellow in color), such that the materials are notaesthetically displeasing and/or do not impair color vision when viewingobjects through the materials.

The optically transparent material can comprise a substrate having afront surface and a rear surface, and a first multilayer dielectriccoating disposed on the front surface of the substrate. Optionally, thematerial can further comprise a second multilayer dielectric coatingdisposed on the rear surface of the substrate.

The material can be in any suitable form which facilitates positioningof the material in the optical path between environmental lightcomprising blue light and the retina of a user. By way of example, thematerial can be in the form of an optically transparent sheet configuredto cover an LED display. Alternatively, the material can be in the formof an optically transparent housing configured to cover or enclose anLED (e.g., a housing for an LED lamp). In certain embodiments, thematerial can be an optical lens, such as an ophthalmic lens (e.g., aneyeglass lens) for use in an ophthalmic system to be worn by a user.

The multilayer dielectric coating(s) present on the surface(s) of thematerial serve to reflect a portion of incident blue light, reducing thetransmission of blue light across the material (e.g., from the frontface of the material to the rear face of the material). In someembodiments, the front face of the material exhibits a maximumreflectance in the visible spectrum of from 5% to 30% reflectance (e.g.,from 10% to 30% reflectance) at a wavelength of from 430 nm to 470 nm(e.g., at a wavelength of from 440 nm to 460 nm). In some embodiments,the front face of the material exhibits a reflectance spectrum having afull width at half maximum of from 75 nm to 125 nm. In certainembodiments, the front face of the material exhibits a reflectance offrom 2% to 18% reflectance at 400 nm, of from 5% to 30% reflectance at450 nm, and of from 3% to 20% reflectance at 500 nm. In certainembodiments, the front face of the material exhibits a reflectance offrom 3% to 18% reflectance at 400 nm, of from 10% to 30% reflectance at450 nm, and of from 4% to 20% reflectance at 500 nm.

The material can have a suitably neutral color so as to substantiallyimpair the color vision of an individual viewing an object through thematerial. In some embodiments, the material can exhibit a yellownessindex of 10 or less, as measured by ASTM E313-10 (e.g., a yellownessindex 7 or less).

Also provided are eyeglasses, including non-prescription eyeglasses(e.g., over-the-counter reading glasses), comprising a first and secondoptical lens formed from a material described herein, and a framedisposed about the first optical lens and the second optical lens. Insome embodiments, the eyeglasses can be over-the-counter readingglasses. In these embodiments, the first and second optical lens canhave the same optical power (e.g., an optical power of from +0.0 to+3.50 diopters) with a set optical center.

Also provided are screen covers formed from a material described herein.The screen cover can be an optically transparent sheet or filmconfigured to cover an LED display (e.g., a transparent sheet configuredto cover a computer monitor, tablet screen, or cell phone screen). Ifdesired, the screen cover can be integrated into a housing for anelectronic device having an LED display. Such housings can comprise ashell configured to surround at least a portion of the electronicdevice, an aperture in the shell that is aligned with the LED displaywhen the electronic device is disposed within the shell, and a membranecomprising a material described herein disposed within the aperture ofthe shell, such that when the electronic device is disposed within theshell, the membrane is positioned over the LED display of electronicdevice.

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic cross-sectional illustration of a material (e.g.,an ophthalmic lens).

FIG. 2 is a schematic cross-sectional illustration of a material (e.g.,an ophthalmic lens).

FIG. 3 is a plot of the reflectance spectrum (percent reflectance as afunction of wavelength) of the front face of an ophthalmic lens (traceA) and the back face of an ophthalmic lens (trace B).

DETAILED DESCRIPTION

Provided herein are materials and methods for mitigating the harmfuleffects of blue light. Disclosed herein are optically transparentmaterials configured to block an appropriate amount of incident bluelight, such that when the materials are positioned in the optical pathbetween environmental light and the retina of a user, the opticallytransparent materials reduce the amount of blue light from theenvironmental light that reaches the retina of a user. The environmentallight can be, for example, a light-emitting diode (e.g., in an LEDdisplay or an LED lamp), a fluorescent lamp, or sunlight.

The material can be in any suitable form which facilitates positioningof the material in the optical path between environmental lightcomprising blue light and the retina of a user. By way of example, thematerial can be in the form of an optically transparent sheet (e.g.,having a thickness of from 0.05 mm to 1 mm, or from 0.05 mm to 0.5 mm)configured to cover an LED display (e.g., a transparent sheet configuredto cover a computer monitor, tablet screen, or cell phone screen).Alternatively, the material can be in the form of an opticallytransparent housing configured to cover or enclose an LED (e.g., ahousing for an LED lamp).

In certain embodiments, the material can be an optical lens. The opticallens can be, for example, an ophthalmic lens. Ophthalmic lenses can becorrective or non-corrective; ophthalmic lenses can also be prescriptionor non-prescription. The ophthalmic lens can be an eyeglass lens (i.e.,a spectacle lens) for use in clear eyeglasses or tinted eyeglasses(e.g., sunglasses). In certain embodiments, the optical lens can be anon-prescription eyeglass lens for use in over-the-counter readingglasses. For example, the lens can have an optical power of from +0.0 to+3.50 diopters (e.g., an optical power of from +0.75 to +3.00 diopters).The lens can also have a set optical center. The lens can also be anon-ophthalmic lens, such as, for example, a camera lens. The cameralens can provide for improved image contrast and clarity without colordistortion.

The optically transparent material can comprise a substrate having afront surface and a rear surface, and a first multilayer dielectriccoating disposed on the front surface of the substrate. Optionally, thematerial can further comprise a second multilayer dielectric coatingdisposed on the rear surface of the substrate.

By way of example, in certain embodiments, the material can be anoptical lens, such as an ophthalmic lens. Referring now to FIG. 1, thelens (100) can comprise a substrate (106) having a front surface (108)and a rear surface (110), and a first multilayer dielectric coating(112) disposed on the front surface of the substrate (108). Optionally,the lens (100) can further comprise a second multilayer dielectriccoating (114) disposed on the rear surface of the substrate (110).

The multilayer dielectric coating(s) present on the surface(s) of thematerial serve to reflect a portion of incident blue light, reducing thetransmission of blue light across the material (e.g., from the frontface of the material (e.g., from the front face of the lens, FIG. 1,102) to the rear face of the material (e.g., from the rear face of thelens, FIG. 1, 104)). The structure and composition of the multilayerdielectric coating(s) present on the surface(s) of the material can beselected so as to permit transmission of an appropriate amount ofincident blue light across the material (e.g., to permit transmission offrom 50% to 95% of light at 450 nm across the material, to permittransmission of from 50% to 90% of light at 450 nm across the material,to permit transmission of from 60% to 90% of light at 450 nm across thematerial, to permit transmission of from 70% to 90% of light at 450 nmacross the material, or to permit transmission of 75% to 85% of light at450 nm across the material).

In some embodiments, the front face of the material exhibits a maximumreflectance in the visible spectrum of from 5% to 30% reflectance at awavelength of from 430 nm to 470 nm. In some embodiments, the front faceof the material exhibits a maximum reflectance in the visible spectrumof from 10% to 30% reflectance at a wavelength of from 430 nm to 470 nm.In certain embodiments, the front face of the material can exhibit amaximum reflectance in the visible spectrum at a wavelength of from 440nm to 460 nm.

The front face of the material can exhibit a reflectance spectrum havinga full width at half maximum of at least 75 nm (e.g., at least 80 nm, atleast 85 nm, at least 90 nm, at least 95 nm, at least 100 nm, at least105 nm, at least 110 nm, at least 115 nm, or at least 120 nm). In someembodiments, the front face of the material exhibits a reflectancespectrum having a full width at half maximum of from 75 nm to 125 nm.

In some embodiments, the front face of the material exhibits areflectance of at least 2% (e.g., at least 3%, or at least 4%) at allwavelengths of light from 400 nm to 500 nm. In certain embodiments, thefront face of the material exhibits a reflectance of at least 2% at allwavelengths of light from 400 nm to 525 nm. In certain embodiments, thefront face of the material exhibits a reflectance of at least 1.5% atall wavelengths of light from 400 nm to 550 nm. By reflecting lightacross a range of wavelengths centered in the blue region of theelectromagnetic spectrum, the contrast and clarity of images viewedthrough the material can be enhanced.

In some embodiments, the front face of the material exhibits areflectance of from 2% to 18% reflectance at 400 nm (e.g., of from 3% to18% reflectance at 400 nm, of from 5% to 15% reflectance at 400 nm, orof from 7% to 15% at 400 nm). In some embodiments, the front face of thematerial exhibits a reflectance of from 5% to 30% reflectance at 450 nm(e.g., of from 7% to 30% reflectance at 450 nm, of from 10% to 30%reflectance at 450 nm, of from 12% to 27% reflectance at 450 nm, or offrom 15% to 25% reflectance at 450 nm). In some embodiments, the frontface of the material exhibits a reflectance of from 3% to 20%reflectance at 500 nm (e.g., of from 4% to 20% reflectance at 500 nm, offrom 5% to 17% reflectance at 500 nm, or of from 7% to 15% reflectanceat 500 nm). In certain embodiments, the front face of the materialexhibits a reflectance of from 2% to 18% reflectance at 400 nm, of from5% to 30% reflectance at 450 nm, and of from 3% to 20% reflectance at500 nm. In certain embodiments, the front face of the material exhibitsa reflectance of from 3% to 18% reflectance at 400 nm, of from 10% to30% reflectance at 450 nm, and of from 4% to 20% reflectance at 500 nm.

The material can have a suitably neutral color so as to notsubstantially impair the color vision of an individual viewing an objectthrough the material. For example, the material can be substantiallynon-yellow. The yellowness of the material can be quantified using ayellowness index, such as the yellowness index measured using ASTME313-10 entitled “Standard Practice for Calculating Yellowness andWhiteness Indices from Instrumentally Measured Color Coordinates,” whichis incorporated herein by reference in its entirety. In someembodiments, the material can exhibit a yellowness index of 10 or less,as measured by ASTM E313-10 (e.g., 9 or less, 8.5 or less, 8 or less, 7or less, 6.5 or less, 6 or less, 5.5 or less, 5 or less, 4.5 or less, or4 or less). The material can be substantially free of dyes or pigmentsthat absorb blue light (e.g., conventional ‘blue blocking’ organicyellow dyes such as a coumarin, a perylene, an acridine, a porphyrin, ora combination thereof). For example, the material can comprise less than0.01% by weight of dyes or pigments that absorb blue light, based on thetotal weight of the material.

The multilayer dielectric coating disposed on the front surface of thesubstrate and the multilayer dielectric coating disposed on the rearsurface of the substrate, when present, can each comprise a multilayerdielectric stack comprising a series of alternating discrete layers ofhigh refractive index materials and low refractive index materials. Byway of example, in certain embodiments, the material can be an opticallens, such as an ophthalmic lens. Referring now to FIG. 2, the lens(100) can comprise a substrate (106) having a front surface (108) and amultilayer dielectric coating (112) disposed on the front surface of thesubstrate (108). The multilayer dielectric coating (112) can comprise aplurality of dielectric layers (120) disposed on the front surface ofthe substrate (108).

Dielectric stacks of this type can be fabricated using suitablethin-film deposition methods. Common techniques include physical vapordeposition (which includes evaporative deposition and ion beam assisteddeposition), chemical vapor deposition, ion beam deposition, molecularbeam epitaxy, and sputter deposition. The overall thickness of the multilayer dielectric coating disposed on the front surface of the substrateand the multilayer dielectric coating disposed on the rear surface ofthe substrate, when present, can range from 1.2 microns to 6 microns.

The number of alternating dielectric layers as well as the compositionof the layers in the dielectric coating can be varied so as to provide amaterial exhibiting the desired level of blue blocking for a particularapplication. In some cases, the first multilayer dielectric coatingand/or the second dielectric coating (when present) each comprise atleast 6 dielectric layers. In certain embodiments, the first multilayerdielectric coating and/or the second dielectric coating (when present)can comprise from 6 to 10 dielectric layers (e.g., 6 dielectric layers,7 dielectric layers, 8 dielectric layers, 9 dielectric layers, or 10dielectric layers).

Each dielectric layers in the coating(s) can independently be formedfrom any suitable dielectric material, such as a metal oxide, a metalfluoride, a metal nitride, a diamond-like carbon, or a combinationthereof. In some cases, the first multilayer dielectric coating and/orthe second dielectric coating (when present) comprise dielectric layersthat are each independently formed from a metal oxide selected from thegroup consisting of chromium oxide, zirconium oxide, silicon dioxide,and combinations thereof.

In particular embodiments, the first multilayer dielectric coatingand/or the second dielectric coating (when present) comprise a firstdielectric layer comprising chromium oxide disposed on the front surfaceof the substrate. In particular embodiments, the first multilayerdielectric coating and/or the second dielectric coating (when present)comprise at least two dielectric layers comprising zirconium oxide. Inparticular embodiments, the first multilayer dielectric coating and/orthe second dielectric coating (when present) comprise at least threedielectric layers comprising silicon oxide.

If desired, the material can further comprise one or more additionalcoatings disposed on the first dielectric coating, one or moreadditional coatings disposed on the second dielectric coating (whenpresent), or one or more additional coatings disposed on both the firstdielectric coating and the second dielectric coating. The one or moreadditional coatings can include, for example, conventionalscratch-resistant coatings, anti-fog coatings, mirror coatings,UV-protective coatings, anti-static coatings, or combinations thereof.In some embodiments, the material can further comprise a hydrophobiccoating disposed on the first dielectric coating, a hydrophobic coatingdisposed on the second dielectric coating (when present), or ahydrophobic coating disposed on both the first dielectric coating andthe second dielectric coating

The substrate can be any suitable optically transparent material,including materials used conventionally to fabricate lenses (e.g.,eyeglass lenses) and screen covers for LED devices. Examples of suitablematerials include CR-39 (allyl diglycol carbonate (ADC)), TRIVEX(commercially available from PPG Industries), SPECTRALITE (commerciallyavailable from SOLA), ORMEX (commercially available from Essilor),polycarbonate, acrylic, MR-8 Plastic (commercially available from MitsuiChemicals), MR-6 Plastic (commercially available from Mitsui Chemicals),MR-20 Plastic (commercially available from Mitsui Chemicals), MR-7Plastic (commercially available from Mitsui Chemicals), MR-10 Plastic(commercially available from Mitsui Chemicals), MR-174 Plastic(commercially available from Mitsui Chemicals), FINALITE (commerciallyavailable from SOLA), NL4 (commercially available from Nikon), 1.70 EYRY(commercially available from Hoya), HYPERINDEX 174 (commerciallyavailable from Optima), NL5 (commercially available from Nikon),plastics commercially available from Tokai Optical Co., Ltd., andglasses (e.g., crown glass, flint glass, PHOTOGRAY EXTRA glasscommercially available from Corning, and high index glasses such asthose commercially available from Zeiss). In certain embodiments, thesubstrate can be selected from the group consisting of a glass, allyldiglycol carbonate (ADC), a polycarbonate, a polyurethane, athiourethane, or a combination thereof.

Also provided are eyeglasses, including non-prescription eyeglasses(e.g., over the counter reading glasses) comprising a first and secondoptical lens formed from a material described above, and a framedisposed about the first optical lens and the second optical lens. Thelenses can have any suitable optical power. In some embodiments, theeyeglasses can be over-the-counter reading glasses. In theseembodiments, the first and second optical lens can have the same opticalpower (e.g., an optical power of from +0.0 to +3.50 diopters, or anoptical power of from +0.75 to +3.00 diopters) with a set opticalcenter.

Also provided are screen covers formed from a material described above.The screen cover can be an optically transparent sheet or film (e.g.,having a thickness of from 0.05 mm to 1 mm, or from 0.05 mm to 0.5 mm)configured to cover an LED display (e.g., a transparent sheet configuredto cover a computer monitor, tablet screen, or cell phone screen). Ifdesired, the screen cover can be integrated into a housing for anelectronic device having an LED display. Such housings can comprise ashell configured to surround at least a portion of the electronicdevice, an aperture in the shell that is aligned with the LED displaywhen the electronic device is disposed within the shell, and a membranecomprising a material described above disposed within the aperture ofthe shell, such that when the electronic device is disposed within theshell, the membrane is positioned over the LED display of electronicdevice.

The example below is intended to further illustrate certain aspects ofthe materials and methods described herein, and is not intended to limitthe scope of the claims.

Examples

A multilayer dielectric coating comprising eight discrete dielectriclayers was deposited on the front and rear face of a standard plasticoptical lens using standard physical vapor deposition methods. The firstdielectric layer in each multilayer dielectric coating was formed bydeposition of chromium oxide. Subsequently, alternating layers ofsilicon dioxide and zirconium oxide were deposited to form themultilayer dielectric coatings on the front and rear face of the lens.Hydrophobic coatings were then deposited on the multilayer dielectriccoatings on both the front and rear face of the lens.

The reflectance spectrum of the front face and the rear face of the lenswas measured using a Filmetrics F10-AR reflectometer. The reflectancespectrum of the front face (trace A) and the rear face (trace B) of thelens is illustrated in FIG. 3. As shown in FIG. 3, the lens reflects aneffective amount of blue light to minimize damage to retinal tissuewhile permitting transmission of an effective amount of maintainacceptable photopic vision, scotopic vision, color vision, and circadianrhythms. Such lenses can be used in ophthalmic systems to mitigate theeffects of harmful blue light, including macular degeneration andcataracts.

The materials and devices of the appended claims are not limited inscope by the specific materials and devices described herein, which areintended as illustrations of a few aspects of the claims. Any materialsand devices that are functionally equivalent are intended to fall withinthe scope of the claims. Various modifications of the materials anddevices in addition to those shown and described herein are intended tofall within the scope of the appended claims. Further, while onlycertain representative materials and devices disclosed herein arespecifically described, other combinations of the materials and devicesalso are intended to fall within the scope of the appended claims, evenif not specifically recited. Thus, a combination of elements,components, or constituents may be explicitly mentioned herein or less,however, other combinations of elements, components, and constituentsare included, even though not explicitly stated.

The term “comprising” and variations thereof as used herein is usedsynonymously with the term “including” and variations thereof and areopen, non-limiting terms. Although the terms “comprising” and“including” have been used herein to describe various embodiments, theterms “consisting essentially of” and “consisting of” can be used inplace of “comprising” and “including” to provide for more specificembodiments of the invention and are also disclosed. Other than wherenoted, all numbers expressing geometries, dimensions, and so forth usedin the specification and claims are to be understood at the very least,and not as an attempt to limit the application of the doctrine ofequivalents to the scope of the claims, to be construed in light of thenumber of significant digits and ordinary rounding approaches.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meanings as commonly understood by one of skill in the artto which the disclosed invention belongs. Publications cited herein andthe materials for which they are cited are specifically incorporated byreference.

1. An optical lens having a front face and a rear face, the lenscomprising: a substrate having a front surface and a rear surface; and afirst multilayer dielectric coating disposed on the front surface of thesubstrate; wherein the front face of the optical lens exhibits a maximumreflectance in the visible spectrum of from 5% to 30% reflectance at awavelength of from 430 nm to 470 nm, wherein the front face of theoptical lens exhibits a reflectance spectrum having a full width at halfmaximum of at least 75 nm, and wherein the optical lens exhibits ayellowness index of 10 or less, as measured by ASTM E313-10.
 2. The lensof claim 1, wherein the front face of the optical lens exhibits amaximum reflectance in the visible spectrum at a wavelength of from 440nm to 460 nm.
 3. The lens of claim 1, wherein the front face of theoptical lens exhibits a reflectance of from 2% to 18% at 400 nm. 4.(canceled)
 5. The lens of claim 1, wherein the front face of the opticallens exhibits a reflectance of from 5% to 30% reflectance at 450 nm. 6.(canceled)
 7. The lens of claim 1, wherein the front face of the opticallens exhibits a reflectance of from 3% to 20% at 500 nm.
 8. (canceled)9. The lens of claim 1, wherein the front face of the optical lensexhibits a reflectance spectrum having a full width at half maximum offrom 75 nm to 125 nm.
 10. The lens of claim 1, wherein the substrate isselected from the group consisting of a glass, allyl diglycol carbonate(ADC), a polycarbonate, a polyurethane, a thiourethane, or a combinationthereof.
 11. The lens of claim 1, wherein the optical lens comprises aneyeglass lens.
 12. (canceled)
 13. (canceled)
 14. The lens of claim 1,further comprising a hydrophobic coating disposed on the firstdielectric coating.
 15. The lens of claim 1, wherein the firstmultilayer dielectric coating comprises from 6 to 10 dielectric layers.16. The lens of claim 15, wherein the dielectric layers are eachindependently formed from a dielectric material selected from the groupconsisting of a metal oxide, a metal fluoride, a metal nitride, adiamond-like carbon, and combinations thereof.
 17. The lens of claim 1,wherein the dielectric layers are each independently formed from a metaloxide selected from the group consisting of chromium oxide, zirconiumoxide, silicon dioxide, and combinations thereof.
 18. The lens of claim1, wherein the first multilayer dielectric coating has a thickness offrom 1.2 microns to 6 microns.
 19. The lens of claim 1, wherein thefirst multilayer dielectric coating comprises a first dielectric layercomprising chromium oxide disposed on the front surface of thesubstrate.
 20. The lens of claim 1, wherein the first dielectric coatingcomprises at least two dielectric layers comprising zirconium oxide. 21.The lens of claim 1, wherein the first dielectric coating comprises atleast three dielectric layers comprising silicon oxide.
 22. The lens ofclaim 1, further comprising a second multilayer dielectric coatingdisposed on the rear surface of the substrate.
 23. (canceled) 24.(canceled)
 25. (canceled)
 26. (canceled)
 27. (canceled)
 28. (canceled)29. (canceled)
 30. (canceled)
 31. (canceled)
 32. (canceled) 33.Non-prescription eyeglasses comprising a first optical lens defined byclaim 1; a second optical lens defined by claim 1; and a frame disposedabout the first optical lens and the second optical lens, wherein thefirst optical lens and the second optical lens have the same opticalpower with a set optical center.
 34. Prescription eyeglasses comprisinga first optical lens defined by claim 1; a second optical lens definedby claim 1, and a frame disposed about the first optical lens and thesecond optical lens.
 35. The lens of claim 1, wherein the lens comprisesa camera lens. 36-70. (canceled)